Hemifacial Spasm Caused by Cerebellar Arteriovenous Malformation and Spasm-Relief after Nidus Removal

Secondary hemifacial spasm (HFS) occurs by a conflict between the facial nerve and intracranial pathology, such as cerebellopontine angle tumor or vascular abnormality like arteriovenous malformation (AVM) or aneurysm. HFS caused by AVM is rare, and optimal combination of treatment options has not been established. AVM treatment with or without microvascular decompression (MVD) of the facial nerve was provided in the previous studies, and the outcomes in terms of spasm relief have been successful. Here, we report a case of HFS caused by cerebellar AVM. HFS symptom disappeared after AVM nidus removal without MVD of the facial nerve.